CA2254681A1 - Heating of a bearing - Google Patents

Abstract

The present invention relates to the use of a phase convertible compound for heating a fat lubricated bearing, whereby the compound absorbs frictional heat generated at operation of the bearing, stores said heat until needed, whereupon the heat is released when bringing said bearing into operation under cold operational conditions. The invention further relates to a method for lubricating a bearing as well as a bearing so lubricated.

Description

If l~O~' '98 1~:3=; SkF P~TEr~rS IjE~ ~46 31 ~ f;~la8y 5.2 .' I
T:~TLE
HEATING OF ~ Bl~ING

r~:F..~C~ ~PTION
5 Te~hn;~l field The present invcntion relates to the heatin~ of n bearin~.

~le object of the prese~t inv~ntion is to obt~ a p~sibilitv of heating a be~ring in order ~o obtain a bleedin~ of ~e fat used to lubricate the bcarin~.

ol]nr~ 0~ inv.-nti~)n ~n startin~ an eqllirm~nt ~t ~ low tcmpe~tur~ co~TIrrliing fi~t lubricahd be~rin~s th~re is a problem 1n that the ~t does not kleed oil in ~ sufficient amoullt to flacil~tate ~ good st~rt and to ~uppre~s hi~ firiction coeffloionb. Thi~ w~ll ~omotim~s res~31t in damages of the beA~ o.~.
1~ burniching, e way of Avoiding this problem ha~ been to u~e ~ lo~ tcmpcl~t~e f"at, i.e. a f~t whick will blced at a l~we~ terllperature than a Iw~lly u~ed lub~icating fat will. However, it has tumed o~ th~t e~ren low-l~;[~Lpc. ~ re fats have di~ic~tios in ~ leeding oil at ~eally low tempe~turcs, 20 i~c. at vcry cold weather con~iti~ whioh may occur in winter ti~e in the ~ordic cuu~ ies, Ca~a, N~Ithern US~, the Arctic, and Ant~ctic area~ as well as no. ~ ku~sia and Asia.

Thus the~e is a demand ~r sulving this problem irl a more e~ficient ~ay.

~5 nescript;~ of th~ pre~invention It ha~ nc~w sulprisingly b~en shown possible to solve this probJem by means o~the present inve~tion, which i5 characterizcd in t~at one applie~ a ~at ab~o~ cumposit~on i~ contact ~ith the bearillg to be heated, th~t the heat abso~i~ composition abs~rbs friction~I ~eat cre~ted during operation col~dillolls, ar~d that said ab~orbcd heat i~ released when putting th~

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, b~nng into o~eration, s~l~h as at the sta~t of a cold en~ine.

Fllrth~r characte~sti~s will be evident *~}xl the accol:npanying cl~ims.

B~ me~ of the present inventio~ hcat will be provid~ to the ~e~nrl~ ~hereby th~ lubricatin~
fai: w~ll be able to bleed oll an~ the~eby to provide ample 1uhrication.

s~ applylng ~ abs~rblr~ medium in or close to the bea~in~, ç.~. in the be~ring house, it is possible prima~ to abso~ ~e i~ictior~al h~at ~ l'U~ in the bearing during operatiorl, to 10 st~re said g~erated heat, ancl to release tho he~t nee~e~ to have a l~bno~tin~ fat bleeding its oil to provide lubr~cation to the bearin~ a~ such.

Irl a prefened cmbo~ment of the irltte~on a salt solLItion is us~d, which p~ses a p~se transition when absor~in~ heat, ~iz, going ~om a so1id state to liqu~ statc whetl absorbin~ he~t, 15 su~,h ~ firictio~al heat, and ~4hich liquid remain~ stable until ~ rersed ph~e transition is initiated. Such an initiatio~ ca~ b~ earried out uqlng a e.g. a mec~ ;c~l vibration of a~y ~pe.
Wllcn ~e phas~ tr~qnciti~n has been initiated ~d i5 obt~ined, he~t will~be re1eace~ as the salt 501uti(~n ~oes f~ uid state to a solid stat~, ~hich heat will vt~alm the lubhcatin~ fat of the b~irle ZO
M~st salts, in ~a~ticular e~stall~nç salts, will fo~h phaae k~ll3Llion system whicli releas~ heat, an~i the ~IlC slcill~d in the art only h~ to deteTminc which one ~at has the n~ost suita~le te".~ b range for its ph~e t~ sition.

~5 Or~e ~llitable ~lt solution i9 ~odium chloride in aeetic acid, which wherl going fro~l s~l~tion to solld ~tate expresses ~uite an anlo~nt ~f }~eat~

S~aring heat in this w~ is already known and carried out in other techn~e~l areas fo~ o~e~
purposes, e.g. so called heating pads. ~hese are used ~or hea1th care, but can also be used for U ~ ~ l C ~ H I ~I I I ~ IJ~- +~b ~1 ~J ~

rapld heating vf hand~ ant fce~ outdoors on eh~lly days.

Thc mcdium u~ed can be applied to the be~Ang In a p~ckage in the beanng housc or be ~ppliod a~ a ~ e coat~n~ on th~ inner w~lls of the bea~in~ hou~e.

The salt ~olution cP~pnse9~sinxles~lt 4r mixture ~f 1~l4I~ ie Ba~ or tho heat ~bsorbln~
~olution ean consi~t of an o~g~ic ~cid or compound which h~s the satne ability of ~b3~.1,ing heat du~ing pha~e con~er~ion.

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Claims (7)

1. The use of a phase convertible compound for heating a fat lubricated bearing, whereby the compound absorbs frictional heat generated at operation of the bearing, stores, said heat until needed, whereupon the heat is released when bringing said bearing into operation under cold operational conditions.

2. A method for lubricating a bearing using a lubricating fat, characterized in that one applies a heat absorbing composition in contact with the bearing to be heated, that the heat absorbing composition absorbs frictional heat created during operation conditions, and that said absorbed heat is released when putting the bearing into operation, in order to make lubricating fat used to lubricate said bearing to bleed.

3. A method according to claim 2, characterized in that said heat absorbing compound is a salt which in solution transforms from solid to stable liquid state when absorbing heat and reverts to said solid state when releasing heat.

4. A method according to claim 2, characterized in that said heat absorbing compound is an organic compound.

5. A method according to one or more of claims 2-4, characterized in that the heat absorbing/heat releasing compound is provided in a package in close contact with said bearing,

6. A method according to claim 5, characterized in that the heat absorbing/heat releasing compound is provided as a coating onto a surface of the bearing.

7. Bearing to be lubricated by a fat and comprising a heat absorbing a compound which is arranged to absorb heat while said bearing is in operational to store said heat and to release said heat when said bearing is brought into operation under cold conditions, whereby said heat released is arrange to cause a fat used for lubrication to bleed oil.